Although it has been demonstrated that various diabetic substrates (including high glucose, glycosylation end products, and albumin), reactive oxygen species, angiotensin II, and TGF-β1 play important roles in EMT and TIF for patients with DKD, insufficient attention has been paid to the role of immunoglobulins in renal interstitial fibrosis of DKD. This evidence concerns the gene AGT and diabetic kidney disease.